Cooper told Chacon prior to today's game against the Tampa Bay Rays he would pitch in the bullpen for the immediate future.

Chacon signed a $2 million deal with the Astros in February after being told he could compete for a spot in the rotation.

"I didn't expect him to be totally happy because he came here because he had a chance to start," Cooper said. "I'm not concerned that he's unhappy because I think he'll do whatever he needs to get it done.

"I'm sure he's not going to swallow it, but he'll be upset for a while and then I'm sure he'll pack his bags and do what he's got to do to get out in the pen and be good."

The Astros will call up veteran righthander Runelvys Hernandez from Class AAA Round Rock to start Friday against the Boston Red Sox. Hernandez is 6-3 with a 3.72 ERA in 15 starts for the Express.

Chacon, 30, is 2-3 with a 5.04 ERA in 15 starts, but is 0-3 with a 9.35 ERA in his last four starts. He'll be available in the bullpen beginning Tuesday.

"I'll handle it like I'm going to handle it, but it's horse ...," said Chacon, who saved 35 games for the Colorado Rockies in 2004. "Plain and simple."

Chacon was moved to the bullpen midway through last year with Pittsburgh because the Pirates' pen needed help. He emerged as an eight-inning setup man.

Chacon was a pleasant surprise for the Astros during April and early May. In his first nine starts, he failed to get a decision but had six quality starts and was perhaps the more reliable starter.

"Yeah, but that was forgotten," Chacon said. "That's long forgotten. I understand the game and you've got to win, but That's all I have to say."

"He's been up and down," Cooper said. "I go back to mid-May, probably since the start he had in Arizona he's been hot and cold. That's basically what we talked about, getting more consistency.

"I don't want to just blame this on him and say he's the reason we're playing bad. If I did that, I would have to point at 25 players plus eight, nine coaches. I'd point the finger and everybody. That's not the case. He's one of the guys that's pitched in the pen before."